UPDATE 1-Biggest shareholder in Spain's DIA raises stake to 29 pct

MADRID, Sept 28 (Reuters) - LetterOne, controlled by Russian tycoon Mikhail Fridman, has raised its stake in Spanish discount supermarket chain DIA to 29 percent from 25 percent in a move likely to renew speculation it could launch a full takeover bid.

LetterOne, which now holds a 15 percent direct stake in DIA and 14 percent indirectly, is expected to clarify shortly whether it intends to seek control of the company.

Under Spanish merger law, the threshold for launching a full takeover bid stands at 30 percent.

The increase in LetterOne’s stake was disclosed in a filing with Spain’s stock market regulator, the CNMV.

LetterOne also said it had brought forward the redemption date for its now 14 percent indirect stake held through derivatives in DIA to Oct. 19 from Nov. 2.

Shares in DIA jumped as much as 4 percent after Reuters published news of LetterOne’s increased stake in the supermarket chain.

The supermarket group, which faces tough competition in its home market from local heavyweight Mercadona and rivals such as Lidl and Aldi, gained ground during an economic crisis which drew more cash-strapped customers into its stores.

But it has been struggling to find the right strategy now that the country’s economy is rebounding strongly.

DIA, which has lost more than two thirds of its market value since a 2015 peak, appointed a new chief executive officer last month and is due to present a new strategic plan by the end of the year.